In 1992, the Institute for Electronics and Electrical Engineers (IEEE) established a standard for a scalable coherent interface {SCI}. SCI supports distributed multiprocessing at high bandwidth, with low latency, and providing scalable architecture. Since the 1980's, there has been continuous development of redundant arrays of inexpensive or independent drives (RAID) which provide fault-tolerant data storage and access capabilities. It is against the general background of RAID and SCI that the invention is made.